It visualises the Soviets exploration of space, projecting forward from existing 1950’s technology to predict first the building of and then everyday life aboard a space station and culminates with a landing on the moon.
It’s propaganda for sure but the effects and model work are an absolute marvel for their time and not bettered by anyone for a good decade after. It is also most probably one of Kubrick’s visual inspirations for 2001.
Its director was one Pavel Klushantsev who would go on to make the equally stunning Planeta Bur a few years later. The man had an eye for film design and it’s a real shame he never did more or indeed received the recognition he so richly deserved.